Not necessarily the best option for traditional dedicated servers but Amazon AWS uses Epyc for their new setups.
I used to use rapidswitch.com quite a bit in the past - don't think they do any Epyc provisioning and I kind of went off them, though didn't have a problem with the service from them, when they sold off a bunch of customers to a 3rd party who weren't very good.
What’s your budget/connectivity/support requirement? Can you give us any other information on what spec/hardware you want/need? Depending on budget/needs you may even find it more useful to rent your own space and put your own hardware in it if you have a suitable DC locally - sadly that varies massively in cost/connectivity depending on where in the UK you are and if it’s only a few U then you’re likely stuck with a reseller rather which can make things more difficult.
If you want to test, OVH will do you a dual Xeon 5118 with 96GB and dual 500GB NVMe for £256.99+VAT in the UK on a gigabit connection, no set-up and rolling contract. A reseller should be able to get you better contract pricing and throw in premium bandwidth etc.