I bought 3 old style Bardwell & McAlister fresnel spots with stands barn doors, snoots, focusing spots, the works from a guy on Craigslist. The lights I was told were made in the 50's and 60's. Also included were a box of 30 750W lamps like the ones shown in the photo. However, other than the standard markings on the lamp I can't find a size or model. Can anyone fill in some gaps for me?