Booboo3131
They're really just junky old bookshelf speakers - which is why you found them at the thrift shop.
PM me and I can help by taking them off your hands for the price of shipping to me.
cwlondon
ps
Just kidding.
Assuming they are in decent shape, your Rogers speakers were a lucky find, and they are one of the great all time classics, particularly in the midrange and/or at lower to moderate volumes.
Having said that, it is my opinion that like say, Quad ESL 57's, they have an occasionally irrational cult following.
This has led to inflated prices on the used market, where one could arguably buy equal (or better?) performance for comparable or even less dollars and get a new product in the process.
The logic of keeping or selling therefore depends on how much you care about audio, and the elusive and magical midrange and balance of the Rogers LS3/5a
Others may know more but just my 0.02 reflecting on a listening session from 1981 and noting used prices in recent years.
Best regards and happy listening