Look for a No.4, Mark II, if you want better condition, better accuracy, etc. It has a trigger improvement over the No. 4, Mark I, and can usually be found in better shape. In the No.4s, the Canadian Longbranches are really nice.
Get a No. 1, Mark III or III* SMLE, if you want history. They're slightly less accurate and weaker in the action than a No.4, but again, they've got that 'look', and the history. British No. 1s are hard to find in clean condition, but you never know what you'll find. I recently found one (1917) that was FTR'ed to brand new in 1953. An older collector had owned it for decades. Nice Aussie No.1s are available, but beware of 'parts guns' assembled by US importers (short serial numbers). The wood on Aussies is also weaker than the Brits, but they're still great.
Last, I like the late model Indian Ishapore No.1s in .308 (late 1960s). They are comparitively less expensive.
With ALL Enfields, check the headspacing. Replacement bolt heads are available to correct minor wear, but it can be an issue. Remember, the Brits fought a lot of battles with these guns. It's harder these days to find good ones. Avoid beaters.
