Just a post to catalogue the lasers used in various consoles, I'll update as I find more information.
Sega MegaCD 2 & Amiga CD32
These consoles use the Sony KSS-210A laser assembly. Spares are readily available on Ebay, replacement will need to have the on-board pot adjusted after installation.
Panasonic FZ-1 3DO
This uses a Sanyo SF-92.5 (11/4 pin) unit. These comes in two types - long cable and short cable.
The 3DO needs the short cable version as the sledge guide holes are 3.5mm whereas on the long cable version the holes are 3.0mm. If not sure if the sledge is easily detachable for the laser unit yet or if the holes can be bored out to 3.5mm.
Most units on Ebay are of the long cable variety, short cable units are more difficult to find.