Yes! You can definitely do that. I’ve just got mine from RSorder and it was a wonderful buying experience for me. I got my 300 Million OSRS Gold within 3 minutes. The process is very straightforward as well, you simply place your order and pay for it.
Once I talked to their support staff, I was given a specific location and a certain character that I should look for and when I went to that place it was pretty obvious who I should talk to first. In less than a minute, my RS 2007 Gold order was transferred to me and I was able to purchase better armours and weapons for my main.