Help Needed re: refund

sarah03_2

Hope i've placed this in the correct place and any help would greatly apprecciated!

I bought my son a mini quadard for christmas foolishly did'nt check it to make sure it worked before the month warranty ran out, Bought the quad from FUNBIKES, discovered the pull start was faulty so ordered another one on 2nd January 2008, weeks passed - contacted them and they advised no stock, managed to get hold of one on ebay for less than half the price (should have checked there first), contacted FUNBIKES to say part no longer needed, phone calls and e-mails back & forth they are now saying that the company was sold and asked for a original copy of the order & payment, I forwarded this to them and they have this morning offered the part or a credit note, I have told them I don't need the part and did not forsee needing to order anything else from them so did not want a credit note - I asked for either a cheque or the money crediting back to the card I paid with, they have now said that they will try and contact the previous owner of the company for this refund!
Surely if they take over a company shouldn't they honour this? where do I go from here? it's only £24.00 but theres a principle involved now
many thanks in advance