Mike just remember if you go classic #4 or 4&1/2 your one blade sharpening system can be done by hand easily. With the thick bevel up you will need a guide ($150) and a second blade ($50) so that's $200 of your budget! There are cheaper guides but mostly for the bevel down. I like the #4 & 1/2 as the extra width means if you round the corners for smoothing big flat surfaces you still have a decent width.
Mastering an old plane is great training you won't regret. You will come back to it all the time.