Lee Enfield .303 advice

I’ve finally received my Fac back from renewal. Got a .303 and sec 1 12g added. Looking to purchase a Lee Enfield .303 first, can anyone advise on what to look out for in these old rifles and what model/SKU? Not wanting to spend a fortune on the rifle because it’s not what I’ll be using very often in competitions. Potentially looking to purchase at the Northern shooting show this year at Harrogate. TIA