It's absolutely fine for that amount of mileage, the one thing to check is whether it's appropriate for how you cover those miles - where you go, what mileage you do in a day, what you normally do for lunch. Also where you are based as that affects charging options.
You say 1000-1500 miles/month, so 50-75 miles a day if evenly spread - like if you are on the road every day covering a local territory. That would be absolutely fine, overnight charging only needed, better in every way than the car you drive now.
Also fine would be if you make long trips to just visit individual clients who may be anywhere in the country - some of them might well be out of range, but if you are making a single long journey then your route almost certainly passes (or can be adjusted to pass) good charging options. if you are driving that far in one go, you'd be happy to stop for at least a coffee en-route so charging doesn't actually cost you any time.
The worst possible pattern is if your miles are condensed in a few days each week where you expect to spend a long day visiting multiple clients with only an hour or so each, and your territory is Wales. This is a killer in various ways. In winter, the pattern of driving for an hour then letting the car cool down for an hour, then warming it up again etc. gets the worst possible range out of the car - on a single long drive it's easy to get fairly close to the indicated range (ie. 200+ miles per charge, depending on model); for the extreme multi-stop pattern you'd still be fine in summer but maybe 30% less in UK winter conditions. If you do need to charge, then with only 50-mile hops between the fixed locations there's probably only one sensible route and if it's cross-country it may not pass (m)any good charging locations; if it's in Wales where there are very few public chargepoints anyhow then you are probably out of luck. Finally, if you are visiting a client every hour then you probably get all the coffee you can drink and so the charging stop is extra time you wouldn't otherwise have spent.
But it's fairly easy to work this out - spend a few minutes with Google maps to look at the mileages of where you went over the past few weeks and check out how those days would have played out in a Tesla. Any days <150 miles, no problem at all; days 150-200 miles, if they happen often maybe an argument that you need a Tesla with the bigger battery; days 200 miles+ check how your routes look against Tesla's supercharger map and the zapmap.com map of public chargepoints.