the cheapest place to buy a vulcan is online off of someone.
tesco
K-mart Walmart
Because they do not sell as often, you can try your best online
As the Red Strike series is long discontinued, you will not be able to find the red Nerf Vulcan EBF-25 in Ohio.
the vulcan certainly looks better, but: the punisher shoots father, has a higher dart capacity, is lighter and cheaper
The Nerf vulcan is already out in toyrus stores for about $50. They are pretty much the same as the others around the world, so you could buy it anywhere and you would still get the same thing.
Unfortunately, you can't in 75% of stores. The only way to get it is to buy it online, or buy the Titan and Hornet separate and leave the Scout out.
Toys R us, sometimes Target.
Yes, you can buy multiple different 25-Dart belts and conjoin them to increase the capacity.
The Vulcan is already prone to jamming, even when not modified. What you should do is throw that in the dumpster, and buy a Stampede ECS-50.
You can buy NERF guns in Argos, Gadgetshop, Hamleys, perhaps Sainsbury's (according to www.ukstockists.co.uk) and sometimes in a local generic toy shop.
I don't want an edit war but I know the Vulcan does not jam. You can buy whichever, but if you like sniping, get the Longshot. If you are into assault missions and firepower, the Vulcan is probably for you. Just make sure to handle the belt feed carefully.