Amp upgrade suggestions

[walrus]

I currently have an SWR Bassic Black combo with a Goliath 4x10 cab. It sounds good but doesn't quite have the volume that I need. So, it's time to look for an amp. I have seen a few used SWR SM-400 and 550x heads in the $300 range. Any suggestions of other brands to look for? I haven't bought anything in awhile, so I need help on what to look for.
I'm looking for a classic rock sound but also not a lot of color (want to hear the RIC characteristics come through).
By current basses are:
76 4001 with toaster and horseshoe with TI flats
09 4003 all stock
08 Jazz Bass with Fralin pickups

Any help would be appreciated.
'

[jps]

Markbass F1 or Little Mark III are great sounding amps with the Rick, they may cost a bit more than a second hand SWR but comparable to new ones. You can find the older Little Mark II used for a decent price which is also a superb amp.

[cheyenne]

GK 700RB II is a good amp for the bux.

http://bass-guitars.musiciansfriend.com ... D=26040176