Tiger 900 Rp Tyres - Where Are They?

Its now time to change the awful Bridgestones for something with a little n=more grip and that make the Rp look a little more adventurous. The problem is finding the tyres. Im going to all the usual websites and putting in the tyre sizes from the current set: Front 90/90/21, Rear 150/70/17.

I cannot find a pair to match these sizes -am I being a complete idiot and unknowingly trying to find the same size when they don't exist? Will the Tiger take a variety of sizes or do I have to still with the sizes above.

Or is it just the fact that supply is tricky ATM? Im looking for metzlers or continental TCK 70's.

Grateful for any advice.