ADSB CAPE

IS THERE ANYBODY OUT THERE DESIGNING A ADSB CAPE FOR SALE ?

I sourced 2 ,but unfortunately one of them is at a rediculous price near 600-800 + euros
The other, the developer does not plan to sell anything ,but will give the plans and software free.
Very frustrating as im new to this and radarcape is advertised as a beaglebone cape ,but has been developed with a box for a windows computer.

If this has been put on sale as a cape ,then ive missed something here
My plan was to compile my kit as a portable adsb unit using beaglebone black and the software that comes with it, dump1090 and a proper 1090 mhz antenna without the use of rtl820t dongle which i have on another tablet .

If anybody knows of a better solution please advise?

regards