I have seen several times that bassmen, especialy pro cats, tend to sound the same, no matter what gear they use.
OK, there are cabs and amps of different voice, but there are mighty EQ on any given amp. You can sculpt your sound like you want.
As I play in different bands I have a variety of different amps like a GenzBenz GBE 1200 with a Tecamp L 215, a good old Peavey TMax with a sealed 410, a Markbass LM II with a SWR Workingman 212 with Beyma woofers, an Ampeg SVP Pro with a poweramp and a Tecamp L 810, and a Bugera BVV 3000 with a Tecamp L 810. Not to forget the Ibanez Promethean 5110.
I play Musicman Stingray basses the most, a Classic 5, a SR 5 and a SR 4 3bd - besides a variety of other 4- and 5-string basses.
Believe it or not, it seems like I sound the same with all my different rigs. Ok, maybe not exactly the same, but as similar as possible. Its not that I desired to sound the same, it just happened.
I had the same problem, my SWR Redhead died in 2006 after more than 16 years of have giging. No chance to replace or repair the beloved amp. Next to the SWR - sound came the Markbass LM II when running the amp flat with the VPF-Filter between 11 and 12 'o clock. This gives you the scooped sound of a SWR. As the LM II/III are no longer in production, I recommend the Big Bang. The Big Bang has a bit more deep lows, but there is an EQ.
Another amp I would like to recommend is the
Glockenklang Blue Sky. The amp is dead-neutral, literaly "a wire with gain", plus a mighty EQ, so you are able to dial in any tone you like.
You like your cabs, is there a need to replace them? If you blow a speaker you can get one for replacement. Are the cabs what is called "road worn"? Is it a cosmetical issue? So make it your project, get some tolex or rat fur or whatever finish there is on the cabs. DIY.
Think about my words. Bassmen tend to have "theyr own" sound, no matter what amp is used. The better the amp (EQ), the more they do.