Yes Kato is a good brand, I don't have any myself though. If the one you bought is new Wow yes you got a good deal. If it is not new I don't know and I doubt if anyone else will with out more info.
Here is Kato USA's website... By the looks of it an HO Scale SD70 costs $150.00 brand new, although they do not have your Conrail engine listed on their site... Not much else I can say since I am no HO expert
This is a Conrail EMD SD70MAC Diesel Engine #4137 (Cab Headlight)
Basic Assembly Required
Equipped w/ Knuckle Couplers
5-pole Motor w/ Dual Brass Flywheels
Detailed Cab interior & Blackened Wheel for realism
DCC Ready w/ NMRA 8-Pin Socket (Decoder Not Included)
I bought this engine off ebay. It is New in the box. Above is the description. the feed back rating is 100%.