sapphire was limited to an amount of 5000pcs if i'm right. and it came out when the pce was almost dead ('95. shortly before the 32-bit age started). therefore it raised up to one of the most beloved collector-items for the pce system, which explains its high price.
usually pce shmups going for between 10~100 bucks, depends how rare and its demand is. there are few others which are settled also above the 100$ mark, just as sylphia, magical chase, darius alpha, 1941 etc. and those special "not for sale" competition versions of gunhed, final soldier, soldier balde.
here's the "inoffical" complete list:
# TITEL Manufacturer RELEASE GENRE 
(Super) Hu-Card 
1 <1941 Counter Attack Hudson 1991 V 
2 <1943 Kai Naxat 1991 V 
3 <Aero Blasters Hudson 1990 H 
4 <After Burner II NEC-Ave 1990 3D 
5 <Aldynes Hudson 1991 H 
6 <Armed Formation F Pack-In 1992 V 
7 <Atomic Robo Kid Special UPL 1990 H 
8 <Barunba Namco 1990 V/H 
9 <Bouken Danshaken Don San-Heart Hen I'Max 1992 H 
10 <Burning Angels Naxat 1990 V 
11 <Coryoon Naxat 1991 H 
12 <Cyber Core IGS 1990 V 
13 <Daisenpu NEC-Ave 1990 H 
14 <Darius Alpha NEC-Ave 1990 H 
15 <Darius Plus NEC-Ave 1990 H 
16 <Dead Moon-Gessekai No Akumu TSS 1991 H 
17 <Deep Blue-Kaitei Shinwa Pack-In 1989 H 
18 <Download NEC-Ave 1990 H 
19 <Dragon Saber Namco 1991 V 
20 <Dragon Spirit Namco 1988 V 
21 <Fantasy Zone NEC-Ave 1988 H 
22 <Final Blaster Namco 1990 V 
23 <Final Soldier Hudson 1991 V 
24 <Final Soldier Special Version Hudson ? V 
25 <Galaga 88 Namco 1988 V 
26 <Gokuraku Chuka Taisen Taito 1992 H 
27 <Gradius Konami 1991 H 
28 <Gunhed Hudson 1989 V 
29 <Gunhed Special Version Hudson ? V 
30 <Hana taakadaka!? Taito 1991 V/H 
31 <Hany in the Sky Face 1989 V 
32 <Heavy Unit Taito 1989 H 
33 <Image Fight Irem 1990 V 
34 <Kyûkyoku Tiger / Ultimate Tiger Taito 1989 V 
35 <Magical Chase Palsoft 1991 H (regular and PCE fan release) 
36 <Metal Stoker Face 1991 V/H 
37 <Mr. Heli no Daibôken Irem 1989 V/H 
38 <Ordyne Namco 1989 H 
39 <Override Data East 1991 V 
40 <P 47-The Freedom Fighter Aicom 1989 H 
41 <Paranoia Naxat 1990 H 
42 <Parodius da!! Konami 1992 H 
43 <PC-Denjin-Punkic Cyborgs Hudson 1992 H 
44 <Power Gate Pack-In Video 1991 H 
45 <Psycho Chaser Naxat 1990 V 
46 <Rabio Lepus Special Video System 1990 H 
47 <Raiden Hudson 1991 V 
48 <Rock On Big Club 1989 H 
49 <R-Type I Hudson 1988 H 
50 <R-Type II Hudson 1988 H 
51 <Salamander Konami 1991 V/H 
52 <Side Arms NEC-Ave 1989 H 
53 <Soldier Blade Hudson 1992 V 
54 <Soldier Blade Special Version Hudson ? V 
55 <Space Harrier NEC-Ave 1988 3D 
56 <Space Invaders-Fukkatsu No Hi Taito 1990 V 
57 <Super Star Soldier Hudson 1990 V 
58 <Tatsujin Taito 1992 V 
59 <Tenseiryû / Saint Dragon Aicom 1990 H 
60 <Terra Cresta II Nichibutsu 1992 V 
61 <Thunder Blade NEC-Ave 1990 V/3D 
62 <Toilet Kids Media Rings 1992 V 
63 <Toy Shop Boys Victor 1990 V 
64 <Twin Bee-deta na!! Konami 1992 V 
65 <Violent Soldier IGS 1990 H 
66 <W-Ring / Double Ring Naxat 1990 H 
67 <Xevious-Fadraut Namco 1990 V 
Arcade/Super/CD-Rom² 
1 <Ai Chôaniki NCS 1995 V/H 
2 <Alzadick - Summer Carnival '93 Naxat 1992 H 
3 <Avenger Telenet 1990 V 
4 <CD-Denjin-Rockabilly Tengoku Hudson 1993 V/H 
5 <Chôaniki NCS 1992 V/H 
6 <Cotton Hudson 1993 H 
7 <Daisenpû Custom NEC-Ave 1991 H 
8 <Download 2 NEC-Ave 1991 H 
9 <Forgotten Worlds NEC-Ave 1992 V/H 
10 <Gate of Thunder Hudson 1992 H 
11 <Ginga Fukei Densetsu-Sapphire Hudson 1995 V 
12 <God Panic-Shijyou Saikyu Gundan Teichiku 1992 V 
13 <Gradius II-Gofer no Yabô Konami 1992 H 
14 <Hawk F-123 Pack-In Video 1992 H 
15 <Hellfire-S NEC-Ave 1991 H 
16 <Image Fight 2 Irem 1992 V 
17 <Kiaiden 00 Telenet 1992 H 
18 <L-Dis NCS 1991 H 
19 <Legion Telenet 1990 H 
20 <Macross 2036 NCS 1992 H 
21 <Metamor Jupiter NEC-Ave 1993 H 
22 <Nexzr Naxat 1992 H 
23 <Nexzr Special - Summer Carnival '92 Naxat 1993 H 
24 <Psychic Storm Telenet 1992 H 
25 <Rayxanber II Data West 1991 H 
26 <Rayxanber III Data West 1992 H 
27 <R-Type Complete CD Irem 1991 H 
28 <Seirei Senshi Spriggan - Summer Carneval '91 Naxat 1991 V 
29 <Side Arms Special NEC-Ave 1989 H 
30 <Space Fantasy Zone (unrelease) NEC-Ave 1991 3D 
31 <Space Invaders - The Original Game NEC-Ave 1995 V 
32 <Spriggan mkII - the terraforming Project Naxat 1992 H 
33 <Star Parodia Hudson 1992 V 
34 <Steam Hearts TGL 1996 H 
35 <Super Darius NEC-Ave 1990 H 
36 <Super Darius 2 NEC-Ave 1993 H 
37 <Super Raiden Hudson 1992 V 
38 <Sylphia Tonkin House 1993 V 
39 <Terraforming Right Stuff Corp. 1992 H 
40 <Winds of Thunder Hudson 1993 H 
41 <Wonderboy III-Monster Lair Hudson 1989 H 
42 <Zero Wing Naxat 1992 H 
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