Looking for a Pre to run into motu m4

I have a Motu M4 which works well, but the mic preamps are not great. From what I can tell inputs 3 and 4 on the back are -16dB line level and bypass the mic pres used on 1 and 2. So it looks like going in via them is the best option. Frustratingly the motu doesn't have an ADAT connection.

I am looking for a preamp or channel strip to run into the back of the Motu m4. Budget is around 500 USD for new (have store credit at sweetwater).

This would be primarily for recording (passive) Bass guitar.

Currently considering the Golden Age Pre 73 and Focusrite ISA One. Anything else I should be considering?