Success stories are only somewhat useful because ultimately what you qualify for is what you will get. Since you are willing to take the HP, and don't want to open a new account, your best bet is to just try and see what happens. Worst case scenario is a decline.
How old is the card, though? The 1k limit shows they weren't very confident in your profile at the time of approval. So if it has only been a little bit of time, may be better to wait. If the account is well established and your profile looks good, take the HP and ask for what you want, and see what happens.
