Superb job indeed. It's not Irish, though, or from 1845; it looks to be a standard font used by the Great Western Railway in England.
I've seen many descriptions of tickets for sale on ebay, or railway signs etc in auctions, which are erroneous, either due to lack of knowledge on the part of the seller, or a fraudulent desire to make it appear more "historic" or "quaint". Also, disgracefully, modern replicas passed off as original.
The above looks very much original, by the way!