Raymarine Autohelm Type 100 ro equivalent

[Boyes]

My Type 100 course computer continually defaults to Standby. All testing shows it is broken.

So looking for a working replacement course computer.

Apparently the following will also work:

Type 400
Type 400G
S3
S3G SmartPilot
SPX-30

If anyone has happens to have a used working one, I'm interested.