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Man, I feel that. It's a magical thing to get those cleans, but as you say, this gear is getting harder to find and that makes it cost more in the process. Not to mention, the gear ain't getting any younger and parts can/do fail.
Have you tried any of the newer ADA pedal based stuff, like the APP-1? I wonder what those cleans are like? I haven't tried them myself
EDIT: Just watched a video, the APP-1 doesn't sound that clean. Sounds more like an actual tube amp (can't believe I'm saying that) with a bit of breakup...not the SS clean you seek.
The MP-1 pedal looks like it's just a dirtbox, so also no help on the clean side
The closest I've come to MP1 or MP2 cleans is running into a solid state preamp (Boss GX-700), but it is a compromise. I still prefer the MP2 cleans over just about everything but I use whatever I can get when playing live & it's good enough for those knuckleheads.
I'd imagine an modeler would be able to achieve this, but I'd need something different than that for gains. You're not gonna convince a 'tube guy' that your modeling rig sounds 'just like a tube amp' - it's just not gonna happen