mooer have quite a range of micro preamp pedals as well, most of the famous amps are accounted for.
there are also plenty of multi-effects units that have decent amp models built in with the added bonus of some effects as well (i used to use a Zoom 3030 back when i was playing electric in church) the newer zoom units are really pretty good, some will include a Di output as well which removes the exttrra connection and frees up a DI box for use elsewhere.
I'm currently researching acoustic preamp/DI units to get a better sound now that we've swapped to IEMs rather than on stage amps (i was using a Trace Acoustic Cube)
Matt