Yep, there's quite a few dirt roads in the Parys area. Got about 20 k's of dirt road fm where we are into Parys (Vaal Eden turnoff on Parys road). The road servicing the small holdings is dirt track, some very rocky areas crossing the koppie. The other side of the river, between Vaaloewer and Barage, another stretch of about 20 k's. Between the tollgate and Parys, 30k plus gravel road (links into the road from where we are). Other side of Parys (Gauteng side) there also is a couple gravel roads.
Maybe plan a trip in December or Jan, ride through Friday/Saturday evening, sleep over and do some riding the next day.