How can users pay for an order that may have been aborted or failed at payment

[sandstorm]

VM2.0.22c on J2.5.16

My site and payment systems all work great, but I have one niggle/question.

If a user goes through checkout and gets to payment page (In my case Sagepay), but then decides to not bother paying or maybe doesnt have the correct payment card with them.
That order shows as awaiting payment or pending.

If the user logs into the website they can see the order as pending in there VM account maintenance page, but cant seem to do anything with it.

I wanted to know is there any way to resurrect that order so the user can then go and pay for it. Maybe some sort of "Pay Now button" so tha tthe user can then go and pay for there order.

Thanks

Andy