as ever Tsax is right on key!
Selmers are lovely saxes, but some of your money goes towards the name. Which is why it is absolutely right of Tsax to suggest you compare with Yamaha and with Yanagisawa.
Lots of professionals use Selmer, but you will find that these tend to be Mk VI models, which are not always easy to come by and command a good price (for a good one)! I haven't tried any of the Mauriat, Trevor James or Keilwerth, though I am sure they are good.
I have had (and still keep) a Yanagisawa A901 - alto - and it is a really nice instrument. There are other models [like the 902 which is bronze] and others going up to the silver if you have a spare £30,000 or so!

No? Ok, praps not that one.
I also have a Yamaha tenor - YTS62, and I really like that as well. Good sound, good mechanism, plays well.
My present alto is a Selmer Reference 54 Hummingbird, which is modelled on the Selmer Mk VI - it is really beeeoootiful and lovely!
The criteria, I think, are: your budget and then which one do you like the feel and sound of? Unfortunately no sax is made specifically to fit a certain hand size. Find the one that seems best for playing, sound and price and at some stage you might need to find a good instrument maker/repairer who can customise. You can buy 'risers' for the side and palm keys to help adjust a little.
Good luck.
ps to Tsax: hope this is fair comment.