I have an old RCA P52937SG rear projection TV. Can replacement bulbs be found?

It is very possible to replace it, but it is difficult for private consumers to purchase them. In addition, depending on the TV, it can be very hard to do the replacement.

I would recommend getting a quote from your local repairman and then deciding if it is worth the cost.

If you REALLY want to try it yourself, you can get parts from sites like this one: http://store.audioholics.com/section/13/1/replacement-lamps---bulbs