The heads alone may be worth $40 or so. Less for the one with the cracked
lens as those replacements are expensive. If someone is interested in the historical value, a cracked
lens could be a deal
breaker.
I've seen these go for a lot of money on eBay too. What really seems to skyrocket the price is the stands. Most of the people who buy those are ones who are going for the "Hollywood Look" in their home, home
theatre, office... Of course, that person may also not care about a cracked
lens (I've even seen sellers market it as a positive, which is ridiculous, but I digress "Authentic cracked
lens is a testament to its long and well-used life... blah blah blah"), so it's really just a buyer's market in whatever they want to pay for it.
Post a picture if you can. If it's a very ornamental Kliegl, or the stands are especially well-made, it could be worth more. Decent single-fixture stands usually cost ~$125 alone, and that's used.
It seems like more people go for a more "art deco"
fixture (ala Bardwell McAllister or
Strand Patt 123 which fetch some money) and unfortunately the Kliegls are fairly utilitarian in design (at least the ones made in the '50s were -- 1920's - you might have something here. Oh, and
lens size matters too if you could provide that. Sounds like you have something that can make some money though.
**Oh and watch for any fuzzy white wires. That's
asbestos. You will want to safely remove that before the sale (search here for safe abatement methods). You can rewire it to
current standards or retrofit a household
socket (but I would keep it close to the original design so it can always "go back"). If it's all-original that's great, but wiring that old should be replaced at any rate. You could also sell it totally unwired so the end-user can put anything he/she wants in there (quartz,
incandescent,
LED,
etc).