I did a quick google last night and only came up with Vitas and the cricket Doctor that I had previously heard off. Neither are close enough to pop in so wanted to find out what people thought so I don't waste money on postage for them to be unspikeable.
We use Brian and Brenda. You pay more to us than you will if you go to them directly. Getting hold of them can be tricky (no email, no website, they answer phone calls/texts intermittently) and they only take cash/cheque/postal order as payment.
We can handle all of that on your behalf without the hassle of having to chase them (took me about 2 months to set up an account with Brian, he was unusually busy at the time) to arrange things. You can also pay us via card or paypal if you prefer.
I would say they can be spiked, with a new piece of sole being glued into place. Won't know for sure until they get their hands on them though. The shoe doctor will probably tell you via twitter whether they can be done.