im just wondering if i go to the local dealer would they sell me some parts ?
Technically yes, BUT probably not
What parts do you need? More likely than not, you could just find them on eBay.
Would simplex hand me a 2099 over the counter if I paid them? There is a local dealer in my town 
No, No, No, No. YOU TALKING ABOUT SIMPLEX, Thats allmost worst the EST…
Let’s try to refrain from brand bashing and just remain on topic, please.
And also, I highly doubt you’d be able to get parts directly from a dealer, whether it be Simplex or another company. eBay or other online sites probably are the best source for collectors.
Companies like Simplex don’t actually have a way to accept payment like that. You’d probably need to set up an account and issue a PO for it. They don’t keep a credit card machine or a cash box at their office… and to set up an account you’re going to need a site address where the Simplex fire alarm is installed. They are probably going to want to send out a technician to install it also.
That said, if you make some friends over there they might give you an extra one from some random job. Couldn’t hurt to ask I guess.
Back on topic, they’re over the counter but you have to go to a supplier. See if you have an ADI near you and call and ask if they’ll sell you stuff directly to you or if you need to set up a business account first. Might not be worth the effort at that point!
You can also find virtually any fire lite panel and all of its components, etc. on many websites for sale just by googling it.
eBay will probably be the cheapest.