I think that the most affordable and best pressure cooker (for the money) is the Fagor. It's about half hte cost of the Kuhn Rikon and works well. The better models are the Duo or Futuro, which has sleeker styling and the steam comes out the top. You can expect to pay between $75 and $150 depending upon where you buy it, which model and whether or not it's on sale.
Location: I live in the Heartland of the United States - Western Kentucky
We bought a Kuhn Rikon set a number of years ago and couldn't be more pleased. It's this duo. We paid about $199 USD for it with no tax and free shipping. I don't remember who we got them from, but you could probably find a vendor with just a nice deal.
We particularly like the second skillet pressure pan because we can do small meals. Love our Kuhn Rikon pans.
Good luck on your hunt.
"As a girl I had zero interest in the stove." - Julia Child
This is real inspiration. Look what Julia became!
I have two Kuhn Rikon pressure cookers, and I highly recommend them. Buy the Kuhn if you can justify the cost. However, I've read good things about the Fagor PCs, which are considerably less expensive. Check Amazon for good prices.
Haven't used a Fagor, so I can't comment on that. However, as I said, Amazon sells them, and there are a ton of user reviews on their site: Amazon.com: fagor pressure cooker
Go to that link and just double click on the stars (or on the number after the stars) under any particular product to read the reviews. I've found that the user reviews on Amazon are generally pretty reliable.
Beyond just brands there is what are you doing with the pressure cooker? A big aluminum is a must for canning but stainless steel is nonreactive if you will have tomatoes in a recipe under pressure. I don't know of a huge pressure cooker that is stainless steel except something that is lab grade autoclave. Given that it maybe intermitent use not every day you may be happy with a simple aluminum one. They are the least expensive and heck you can pass it on if you want to upgrade. By the way I like the book cooking under pressure for a start in pressure cooking.