Diamond ring for sale or swop in Oudtshoorn, Western Cape for sale

I inherited a diamond ring from my late ant, recently valued at R53500. As was explained to me, this is the minimum, someone wanting to buy a ring like this one, will pay for it at a jeweler. The immediate resale value is between R16000 and R25000, depending on whom you deal with. I advertised it on Southafricanlisted for R25000, but have not had any serious interested parties 
I need a second car, or the cash, more than I need the ring and therefore looking to swap with somebody wanting to part with his or her vehicle of similar value, who does not necessarily need the cash. To put it in a nutshell, this is a bargain for anybody in need of such a ring, but not for somebody who thinks that it can be sold easily for R53500 
The following is a description of the ring, as per the evaluation certificate in my possession, recently valued by Jewel Afriq, also trading as Bosman Jewellers in the Tygervalley Centre in Bellville, Cape Town at R53500 
One 18 ct yellow-gold diamond ring set. The setting is “Angel”. The center diamond is 0.82 ct and color K, VS2. The smaller stones are 30 diamonds of 0.01 ct and 8 diamonds of 0.03 ct., with a total mass of 0.54 ct. The total mass of the ring is 14 gram