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The only PCMCIA compatible drives I know are the Commodore CD1200, Reno and Archos Amiga CDROM drive. All long out of production
You can get a second hand SCSI CDROM with Squirrel and use that with the A1200 but as you have found, they will be around £60+ as a package.
Another alternative to a CD drive is an
A1200 PCMCIA to Compact Flash adapter to be used in conjunction with a PC/Mac. With an appropriate CF card you could transport potential large amounts of data to your A1200 from a CD inserted into a PC/Mac.
A good option is a PCMCIA Network Package, either
Wireless or
Ethernet Wired. All our cards come with EasyNet which allows you to access shares in the PC and transport data straight from a CD drive. It would displayed on the Workbench as if the CD drive was local to the A1200.
Finally we have
external CD drives for use with the Subway A1200 USB adapter.
Hope this helps!