Hi,
I have coded many of vbulletin gateway plugin and can give you bitcoin payment gateway(bitpay) quickly as it is ready tested ok by a few clients.
It will cost you 160 pound or equivalent, BID here includes freelancer fees too.
Other gateway plugin i have ready are :-
1) Paymentwall
2) GoogleWallet
For stripe have coded for wordpress but if require can convert to vbulletin.
NOTE: Bitpay API IPN require a secure(https) callback url, so your site needs to be on "https" otherwise bitpay will not send IPN callback, so make sure you have https ready before utilising callback or IPN.
My demo site has not https, so i can show you for rest feature but not IPN.
Let me know if any query.
Thanks
Regards,
Pankaj Shrivastava