Spoke Size / Spoke Length Database - What size spokes do I need?

Hi there, I'm building a wheel and I calculated the lengths at left length 292.8 right length 291.3
Johnnyringo has some 290mm ACI Alpina S/S DB Spokes. Would they do the trick?

It's almost 3mm difference on the right, is this a problem?

Thanks in advance for your help.

Rounding down (OK some round up) < 2mm is the number usually banded about as an exceptable margin. You stand a very good chance of having to few threads engaged in the nipples. The right length would be fine though.