Clear resin for glass reproduction

I am posting this request on behalf of a fellow restorer. We are
looking for a clear resin to make reproduction of a firing glass (a
british nineteenth-century military glass artifact found on our
historical sites). We have tried  a resin called Mara Glass but it
yellows after a while and does not prove to be satisfactory. Do you
know of a resin which does not yellow, stay clear, transparent that
could be suitable for reproduction of clear glass. Thanks,

Jean Etcheverry, restorer
Parks Canada
Quebec Region
3 Buade, C.P. 6060, Haute-Ville
Quebec (Quebec) G1R 4V7
Canada

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                  Conservation DistList Instance 9:50
                Distributed: Saturday, December 23, 1995
                        Message Id: cdl-9-50-013
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