I would suggest talking to CryptoCard.
http://www.cryptocard.com/products/c...%2Dstyletoken/
I've been using their tokens and CryptoSHIELD for a couple years now for remote VPN access, and they are the most reasonably priced Solution I have found.
The tokens do NOT expire (unless YOU set an expiration date on a token)
The batteries in the tokens are replaceable.
So theres no forced token replacement costs like you would incur with RSA and some other token suppliers.
For the solution we implemented it was roughly $100.00 per token Min purchase of 5. Plus we purchased an initializer and a few software tokens as well. That provided the licensing and the physical keychain tokens. the server side software and the initializer unit.
I wouldn't have been able to touch any other solution for an entry price like I got from CrypoCARD.
Their tech support has been excellent as well. We called during our free trial, and once or twice during implementation after we decided to go ahead with the purchase.. since then it's been smooth sailing.