1972 Wr250 Piston?

Hello fellow "Vintage Left Kickers",

I am in the midst of starting a restoration on a 1972 WR250 and am trying to find a source for a 0.5mm or 1.0mm over-bore piston kit. Vintco lists everything except the '72 WR250. Is there something special/different about this piston besides the stock bore being slightly different? My bike looks to have the stock bore(?) with a stamp on the top of the piston of "69,43". (I'll post some pictures in a little bit.)

Can anyone educate me or steer me in the right direction on this? I'm hopeful that someone makes a piston so that I don't end up having to source a NOS over bore.

Thanks in advance for your help.

Photos attached.

HVA Parts Book shows the same part number for a CR and WR piston. What is your engine #(First 4 digits)?

Nothing different about your piston or its bore. 69.43 is the stock bore. Vintco's 69.50 is what they believe the cylinder bore should be. BTW, they show a piston for a 1972 250WR in their selection.

Thanks! I went ahead and ordered the Vintco and received it in less than 3 days! Looks to be an exact match. (Except for the 1st over bore of course.)