I have tried the likes of Binance and Bitterex, but they aren't accepting any new users at the moment.
Poloniex have been processing my photo ID for over a couple days now, has anyone got any recommendations for alternatives?
These exchanges are now accepting new traders I guess, because it hasnt been that long that I signed up on Binance and everything worked out successful, no stress

. Maybe if you have not tried again since then, you can give it a try now and see whether they work for you.
Between these are not the only exchanges there are, there are so many other exchanges that you can try, you can as well DEX's, they are different from centralized exchanges, although they dont have that simplicity you will get from making use of CEX, it requires some level of experience to be able to trade on DEX.