Spoke nipple sizes '72 wr250

Does anyone know the nipple size on a '72 wr250 rear wheel and also where i could get originals from?
I've managed to source some NOS clover spokes but they didn't come with nipples.
They seem to be 3.5mm so i could just buy modern ones if need be.

I took my wheels to SFX wheels to be re anodized and the hubs powder coated.
They laced the back wheel like a standard wheel so the spokes fouled the sprocket bolts. When i looked into it i found out that these Huskys have a unique spoke pattern with 3 different length spokes. He had binned the shortest spokes in favour of using just two sizes but he told me he had to replace some as they were seized but i'd already oiled them and unwound them all a few turns so know they weren't.
All the spokes replaced were the shorter length spokes funnily enough. I asked for the original ones back but he said they had been thrown out.
The rims were so bad after acid dipping i've had to buy new morad akront rims.
All very disappointing as I wanted to keep the bike as original as possible.

Buchanan wheel should be able to help you.

www.buchananspokes.com

Ok thankyou, I've emailed them. Do you know if there should be an offset built into to either wheel?