I bought a used Butet saddle and it has held up very well for me. It is very comfortable and a used one can be found between $1500-$2000. It is quite light and has fit all of the horses I have ridden throughout the years.
I have a mondega (the Greenhawk brand in Canada), and I really like it. Tekna saddles look nice, and a good option if you're open to synthetic saddles. I also really like Santa Cruz.
Affordable is a very relative term though. For some people an affordable saddle is $400-600, and for others it can be $1500-2000.
You also have to look at what your needs are from your saddle. I think it's worth investing in a good saddle that fits you and your horse properly to benefit your riding in the long term. You can have a saddle for many years with proper maintenance, so depending on your needs and situation, it might be worth it to save up a bit of money.
You should also look second hand! There are lots of gorgeous, lightly used saddles that can be bought for a fraction of their retail price. I paid half of the asking price for my saddle, and it was basically brand new when I got it.
Do your research and take your time. Don't feel like you have to buy the first saddle you see. It can sometimes take a few tries to find one that works for you. There are also tons of brands of saddles, all with different features. The more you know what you need from a saddle, the easier it will be to narrow it down. For example, if you're interested in hacking and outdoor riding, and not interested in a lot of maintenance, you may look for a full grain leather or synthetic, rather than a calfskin saddle.
Above all, look for a saddle that fits you. If you get an inexpensive saddle that doesn't fit you or your horse properly, it can seriously hinder your progress or your horse's well being. Speaking from personal experience here!
I have a Pessoa and it's been great for me! Not super expensive, which also means it's not the highest quality, but it is very comfortable, fits my horse well, and pretty good in general!