The Trial Versions of the Baroque Organ from Szentgotthard has a limited compass of C2-C3 (048-c to 060-c) in the pedal, C2-G5 (048-c to 079-g) in the manuals. All other functions work.
Free download the Baroque Organ from Szentgotthard HW demo sampleset! (835,9 MB)
The price is only € 59.
I suggest you buy only after trying the demo.