Race Directors, and any others with input, thanks in advance!

I help plan a Sprint/Olympic Tri and we are in the process of finalizing our 'swag bag'.

We are looking at adding a pair of running socks for each athlete. Does anyone have good insight/connections on the best approach to get this done. Our local running store isn't stepping to the plate and the timing isn't appropriate to approach a larger sports store in our area. (Shirts, bags, etc with sponsorship info has already been ordered so couldn't give them credit.)

Any national vendors etc to approach?

thanks!