Stefano, some food for thought.
You are starting out with your enlarging using RC paper. This paper doesn't really need a four bladed easel to hold it flat. Most RC paper especially what you are using, Ilford MGIV Deluxe / Satin. Ilford Multigrade is the same that I use. Sometimes the paper comes out with a slight banana shape, I just gently roll it on either side to straighten it out and I'm off.
When I use this paper (8x10" 203x250mm) I use a flat board (chip board) with a small lip attached on two sides. I marked out the majority of paper sizes up to 400 x 500 (12x16") and put 4 small rubber feet on. It's great for all of my RC paper work and I made it about 15 years ago.
The Beseler Easel in the picture looks pretty similar to some other brands I've seen in this country, but at a starting price of nearly $200 Australian I think it's not on the cheap side.
For your early darkroom needs, possibly a Jobo Varioformat easel could be quite handy, especially for doing tests and multiple prints on a single sheet of 8x10" paper. I have one of these as well and basically it gets used for making all sorts of different pictures on a single sheet of paper often. Check out one of these by googling.
Mick.