Trying to find a pre built machine has been tricky. You can easily get a gaming ryzen machine with glass sides and covered in LEDs to show off the 2070 gpu. Not something suitable for an engineer to run simulations in their office which wants lots of cores, plenty of fast ram and the cheapest GPU that can take three display port monitors.
For servers the range seemed quite limited and high end, and at this point I just wanted some cheap tat for a test environment. So in the end I threw a 3400G on a B450 board and put it in a 2U case.
PC Specialist were pretty much the only game in town for buying the workstations, but their RAM was tripe for AMD use so they struggled to supply 3200MHz DDR4. I hope by now they have found some sane ram. But hats off to them for at least doing an AMD workstation build.