Remember, a QVL is not an exhaustive list - it's simply what the manufacturer's have tested/verified.
That's not to say any other given kit will not work.
What are you specifically looking to use this rig for?
1. Different workloads will require different RAM configs.
2. A 4GB 'kit' is really low by modern standards. 8GB (2x8GB) would be more 'mainstream', with 16GB being the typical 'sweet spot'.
Ryzen compatibility has improved dramatically since launch. Realistically, any mainstream kit from a reputable brand *should* be fine, with speeds up to ~2966MHz, although there are slight risks. Just ensure your retailer of choice has a solid return policy.
Also note, Ryzen will benefit from faster memory (3000MHz/2966MHz kits being the 'sweet spot' here), faster, if they'll work, can be beneficial, but that's in diminishing returns territory.
FWIW, the A320 chipset is a bit of a disservice to Ryzen chips IMO. They really do benefit from OCing (and it's pretty easy to do, too). That's only an option on B350 or X370 chipsets....