How bad do you want it? Do they come up for sale often in your area? He's asking $150.... go look at it, talk to the owner, look around the shop while your there and make the lowest offer you feel comfortable making I have found some really nice stuff that I wasn't looking for just chatting with the seller of something I'm slightly interested in.
The missing guards would cost over $200 to replace.
The stand is heavy, but nothing special.
I wouldn't think it should sell for more than $75~100 tops.