A Czech friend of mine didn't realize she needed a visa and came for a 3 week holiday, only to get 2 weeks on arrival. She is willing to do a border run as she realizes she cannot extend, but will she get a second visa on arrival if she goes to the Burma border?

Most border crossings can issue a visa on arrival but have no personal knowledge of Ranong - phone is listed as "Amphoe Muang Changwat Ranong 85000 0-7782-1216 " on immigration web site.

Is she sure Immigration will not supply a 7 day extension of stay?

She was told no extension by the Immigration officer at the airport. She has the onward ticket and funds however.

Must ask, she is worried she can only get the one VOA, is it restricted or will it be no problem getting a second one assuming Ranong issues them?

It is not listed anywhere I can find as restricted and that would make travel very difficult and seem to defeat the purpose of the visa (for those without easy access to Thai Consulate). Believe she needs to contact an immigration office to be sure. The MFA website for that type of visa is http://www.mfa.go.th/web/2482.php?id=2491 but it is Immigration that issues them. She might make a quick trip to Penang for a tourist visa as no visa is required for entry to Malaysia. But believe a phone call to immigration may be the best bet.

she can overstay 6 days and pay some 2500 baht - still cheaper than visa run.

only some, the major ones, land border crossings do issue VOA - but not the nong kai from Laos or the rail one from Penang.

Local emmigration office will extend for 10 days if given a reason (illness)