You'd have to google it, but some guy started doing them with some wood and a simple c-clamp.... Can't get much cheaper than that. Otherwise there are some universal ones on Brownells and such..
Personally can't see any reason for them unless you do a lot of sights. Just use a brass punch and mallet. In fact, a punch that has a hard rubber coating even better. I've done at least 6 guns and never an issue...
A set of padded vise jaws and drift them out. Brass punch is okay as is aluminum but leaves transfer of metal. It can be cleaned. Make it less by using a number 2 pencil and rub it thick into the side to be struck.
Delin tipped punches are the best I think. Dawson Precision sells them.
Kimber well known for extremely tightly pressed in sights that difficult to remove. If you can't get it out and are going to replace it anyway , you may have sacrifice it rather than damage the slide by milling it out. If you have no mill make a deep relief cut with a hacksaw to relieve the pressure.
I bought one on ebay and love it...you'll need to learn how to use it because it comes with different length pins to completely remove the sight...short learning curve but necessary....sold by 4x4machineshop...49.98 plus 5.80 shipping if memory serves me...from Poulsbo,Washington state