I'd 100% recommend the SMD adapter board route. There is much less risk of getting counterfeit parts (a big problem), and the Vp & Idss specs are much more consistent. I had 100 of
these SMD adapter boards made at JLC PCB for less than $10. It has sides for DSG and SGD pinout, but none of my SMD JFETs have been the correct pinout for the SGD side. The DSG side works great though, and has the pinout labelled on the silkscreen. If you go to "Action" -> "Download", you can download the Gerbers and order them from your fab house of choice.
The boards + transistors will run you quite a bit cheaper than through-hole JFETs, especially if you buy a bunch:
- ~$1/each for less than 10
- ~$0.50/each for 10-100
- ~$0.30/each for 100+
You can get SMD 2N5457s (MMBF5457) at
Digikey,
Tayda (currently out of stock) and even
Amazon (I've purchased these & they tested fine, but YMMV)
You can get SMD J201s (MMBFJ201) at
Digikey,
Smallbear,
Tayda, and
AES