OK, that's better. For the 50's and the Pennsy area, GP-7's, GP-9's, Alco's, and F units were the most likely engines you'd see. You can get a Bachmann FT in NYC paint scheme with a DCC decoder already installed for about $50 at many on-line hobby shops. If you like Alco's, you can get a nice RS-11 that's DCC ready from Atlas in Pennsy colors for around $80. E-bay often has very good deals on older Athearn GP-9's that run perfectly well but aren't up to the detail level of some of today's locomotives. If you want to expand your fleet, you can pick them up for as little as $15. The Pennsy was a popular railroad so it's often possible to find them in Pennsy paint.