Agreed, if you're concerned about parts availability etc... yeah, these may not be for you. Though the Wests and Stohrs are better than all others for that, excepting the Radicals. Stohr is still around...
https://stohr.com/
$10-15k for motors, those are pro built. I've refreshed my own GSXRs for around $2-3k in parts, which is still around what motors complete cost last I looked (noting that I'm still on the old '08 spec).
But if you're looking to just replace, not upgrade/design/develop parts as you go... yeah, a SRF or FE2 might be more your pace... or at least the next transition while you get used to this world... I moved up from door slammers (ITB), and the climb was steep and challenging. But that's what I was looking for.
Plenty of P1's and P2's run at RA... we'll be back out there again next year, ourselves... just look for SCCA weekends! Though seems like the season's pretty well over at the moment.
P2 has GOT to be cheaper to run than P1... I keep telling my wife that... slower, safer, and cheaper!
