Gun Show Options - Yes Or No?

SPDRs & Derivatives Are Strictly Verboten!!

I've been going to gun shows for at least 30 years, and I can't believe this idea has just occurred to me...

Can you put down an option with a dealer?  Is that sort of thing even done?

Let me 'splain...

Let's say I've got a wad of cash, and I'm going shopping for one particular item at the Gun Show.  I've got 8-10 items constantly on the "WANT" list, but this trip is earmarked for, oh, let's say a Colt Commander in .38 Super.

If I can't find that particular smokewagon, I'm open to acquiring a .50-90 Sharps repro or a .458 SOCOM AR upper, but my hopes are on the Colt.

So, enter the gun show.  Got that bundle of Franklins making a smoky spot in my jeans, and there's 10 acres of table space in front of me.

Suddenly, there it is, on the 3rd table inside the door...  A pristine Sharps repro in .50-90, complete with micrometer sights and all the trimmings for only $1500.  It's got reloading dies and a gunnysack full of brass.  Seller's even wearing a hat saying "CASH MAKES ME BARGAIN LIKE A DRUNKEN WHORE"

Damn.  I want it, but that's not why I'm here.  I want to come back and get it if I can't find the Colt, but you & I both know it'll be a gone pecan as soon as I turn my back.

Can you offer an option to the seller?  F'rinstance:

"Mr. Seller!  I truly like the looks of that Sharps.  I'm inclined to buy it.  Here's my wad of cash to let you know I'm serious.  If I offer you a pair of $20 bills, could you be persuaded to take that Sharps off the table for the space of 2-3 hours while I look at the rest of the show?

If I don't see my heart's desire, I'll be back inside of 3 hours, and we'll apply those Jacksons to the purchase price.  If I don't show, you've got that $40 for your time & trouble, and you put the rifle back on the table."

Has anyone ever done this?  I'm just curious.  It seems worthwhile if you see a great bargain, but you're trusting the seller to follow through and not "forget" who you are.