Okay, I'll apologize profusely if the gentleman advertising delivers the goods but I call flaming BS on this.
First, issue I take is India was a backwater dump in the 19th century and two types of guns were typically used/possessed over there. 1.) Mediocre guns by Rodda, Cogswell and other tier-2 and tier-3 makers that could be afforded on British Officer's budgets. 2nd would be the world's finest best guns made for Maharaja and Maharani. The inventory list does not seem probable to be offered for sale in India.
Second issue: I find the statistical odds that the double guns are all .500s and .450s to be extremely dubious. Most guns in India were .450 3" and BPE cartridges along with a huge number of oddball cartridges. So the distribution of calibers is highly suspect.
Third issue: Someone with guns by many of the makers enumerated would not post them in a big yard-sale format from overseas onto an Internet forum.
Fourth issue: A professional would state their prices, a scammer wouldn't know what to charge so he would post them vaguely as above.
Fifth issue: The serial numbers are all a bunch of BS. Examples: Stephen Grant's first known serial number was in 1866 and was # 2480 but you're selling #227. W.W. Greener never made a gun in the 14000 serial number range and yet you have one. Rigby Serial #13545 which would put it at 1870 and likely would be a percussion gun yet you state it's a .500 so I call BS on that. I have no more time at moment to shred the serial numbers but I call mega BS. Joseph Lang serial number #3528 would put it at year 1868 and hate to tell you, but .360 cartridges didn't exist in 1868 for Lang single shot rifles. Lang hadn't even devised the breech loader yet as he was still marveling at the lefacheaux action he'd just seen in France and was bringing back to England at that time.
Sixth issue: You have absolutely no idea how to ship a gun to the US and that it requires a BATF form 6 and about a year of import time. Anytime I buy foreign guns I pony up and buy A LOT OF GUNS at one time because the import process and costs are prohibitive to buy "a gun" and no respectable dealer would advertise them ala carte.
Seventh issue: As related to the 1st issue, the distribution of manufacturers is all wrong. The fact that you don't have more steaming piles of crap from Birmingham is dubious. The fact that 1/3 of your inventory wasn't at minimum marked Army Navy Cooperative Society Limited and Rodda of Calcutta is totally bizarre.
Eighth issue: No such person / maker as E. R. Reilly. E.M. Reilly was the correct answer.
Ninth issue: Any self respecting Desi would know that Indians are perceived as Internet scammers on high-dollar merchandise and you'd have worked with a reputable importer like what occurred when Griffin and Howe uncovered a major trove of fine guns in India in 1991. You wouldn't sign up for an account on a safari site and try to pass them off on your 6th post to people on other continents.
Tenth Issue: Your Facebook page has no friends and one like. It features pictures of some Indian swords but no breech loading guns. That's weird. Both your referenced websites are non-functional...that's also weird for a fellow with $150,000-$250,000 in British guns and you live in a country where web developers to build your site can be had for $5 a day...it don't add up.
Good day Sir!