RGV250 VJ21 and VJ22 yes definately, not the VJ23 though.
TZR? Original parallel twin yes, not the rev cyl or v-twin ones though as far as I know, definately not bought into the UK anyway.

No idea what they go for over there, UK prices are around 2000 euros for a '21, maybe over 3000 for a '28 if you can find one.

I've never seen a good engine in one piece for sale.
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