No 'locate' button when trying to attach proxy files

I created proxy files for C300mkii footage on ingest. All good except that Premiere crashed so I had to do a 'force quit'.

Now I'm trying to attach the proxy files manually, but when I Ctrl-click/Proxy/Attach proxies I'm led to the usual media locating panel where the original file (not the proxy) is preselected but with no way for me to manually navigate to the proxy files (I know exactly where they are). How do I manually navigate to reattach my proxy files?

Thanks!