Stock 250 is about 145hp, where the 292 is about 155 per the chevrolet archives. however I dont/wont/cant stay stock.
Goal is 200hp on a 250. Cam, intake, carbs, exhaust will run about $800 used, and about double new. That doesnt include other incidentals.
Looking like a vortec 4200 may be less expensive in the long run. (unless someone has some 250/292 parts that they are willing to part with)