Fantastic project Bojan, I have always been interested in building a dish.
As a Radio Technician I wanted to take that step as well, and lo and behold 4 weeks ago found a dish up for auction and bought it for $10.00 but fees.
I have removed the aluminium mesh panel and the frame though is in excellent condition.
Thanks for the information on the LNA, typical Astronomy LNA are the most expensive
One thing as part of the auction I received a heavy duty mounting bracket and the linear motor for adjusting.
I cant really start it yet as the woodwork shop requires my attention along with my rental observatory, only 1 month to go before starting new semester at Uni so I think my time is wearing thin.
I am curious though your feed mount is very low, my calculation have place it fair bit higher. I am using the Parabolic Calculator V2 but I only made rough measurements so far, I hope to make a horn antenna as well.
Good luck with yours not sure if I can offer suggestions, I am at the same point in understanding as you.