How do I work out if I can take online retailer to small claims court?

[ThisMustBeMyDream]

I purchased some children's suits on the online retailer sirri.co.uk. They were returned, and they did apparently refund me. However my useless bank returned the money to them instead of forwarding the payment under the current account switch scheme (payment was refunded 18th May, account closed on 19th as it switched to a new current account).
As a result sirri are refusing to engage in any conversation of sorting the refund. They only have an email address and an online chat. The phone number does not work at all. The bank are being equally useless really in saying I need to deal with it - they are washing their hands of it because they sent the money back and my account is closed (I've tried to open a dispute with the bank but it is proving very difficult)
I'm at a loss. If I need to - can I take this company to the small claims court for my refund? The whole situation is ridiculous and shouldn't have happened. But sirri are being as unhelpful as the bank!
There is some suggestion that this might be a Chinese company. They have a uk address on their website. Linked in suggests they are based in Dudley. How do I find out? And if they are Chinese, can I still fight this?
I'm not giving up without a fight!

Send a formal complaint to the bank and if they still don’t sort it to your satisfaction, take it to the FOS (the bank will give you FOS rights after they close your complaint)

Sirri is not a Chinese company. If you scroll down to the bottom of any page on the website, you can see on the left of the bottom banner that their company name is Bordo Ltd. They give their company registration number (which is correct) and their address. You can pursue both your bank, who should have forwarded the money to your new account, and Bordo, who have your money due to the bank's mistake. You should be able to get your money back from one of them.

I wouldn’t waste your time pursuing it with Sirri/Bordo - your dispute is with the bank for mishandling your money. If the bank wants to reclaim it from Sirri/Bordo that’s their problem.

I am trying to fight it with the bank currently, but it's very very difficult! The closed account is causing all sorts of problems. I'm reliant on them filling in thr dispute form. I did it on 24th May over the phone, and it was never even put in on their side (I've no way to check this!). Did it again yesterday, but the man in disputes needed to escalate it as it wouldn't go through. I did take his name and he did seem like he would follow it through, but he said it would take until the middle of next week for an update. It's ridiculous!
Current account switch guarantee my arse!

It's the banks fault. The firm refunded the money which means they kept their side of the contract. Take up the dispute with your bank. You could try the Bank ombudsman if you are getting nowhere with your bank.

You’re not reliant on them - post a complaint letter to them yourself. Which bank is it?