Back in the days when I shot slides, I used to bring my transparencies to LSL Photolabs on Lennox St. to get prints made using their LED printer. The results I got back were even more stunning than Ilfochrome prints (and less susceptible to damage too!)
jessops are a nightmare, i had slides printed in there before and they printed them back to front, out of focus and about a stop and a half too dark. i would avoid them completely. you could try elser crawford on the lisburn road 9032 6999, he does laser printing but it will be expensive