You could, but any gain would either reduce the debt of that particular creditor in the IVA, or form a windfall whicha all creditors would benefit from.
If you use a claim company it would probably charge you, personally I would not bother because as they say the only people who will benefit are the creditors anyway, unless you plan to return the full debt to them with interest in which case it may be worth pursuing.
We're willing to wipe the slate clean, give you a fresh start. All that we're asking in return is your cooperation.