Hope it’s not that one on eBay
To restore a cab it usually involves spending a lot of hours and work to bring it up to a decent standard. The cost of labour and potentially souring hard to find parts might be worth more than the cab. This is why people restore cabs themselves, they can do it at their own leisure and source replacement parts as and when they find them.
Is your cab complete with nothing missing or badly damaged? If it only needs a small amount of work then maybe someone might take it on for a reasonable price. If there’s going to be a lot of work involved then it might be quicker/cheaper to sell your cab as it is and buy another one that’s already fully restored.
To be honest, I don’t know anyone who offers a cab restoration service.