Well, my male burm who was fed well (not too much not too little) was right around 6' at his first birthday. A 7' 4 year old burm is severely stunted. I would consider a snake like that a rescue. You would want to take it to a reptile vet to check it out anyway.. make sure it doesn't have parasites, as that can stunt growth even more. Even so, with good husbandry this snake could still grow.. remember, burms can top 200lbs and 20'. Males even get to 15' and 100lbs or more.

$150? Well.. you can buy a healthy baby for around $65. This animal has been neglected.. it's up to you, if it's worth it to you, then go for it.. just know all you can before you take the plunge.