Could someone please help me with any meaning, origin and pronounciation of these names?
Crimthain
Sairlaithe
Eanlaith
Keefe
Muirean
Galvin
Labhras

Dia duit,
I was able to find all of the names in "Irish Names" by Ó Corráin & Maguire and "Irish Names & Surnames" by Woulfe. In the interest of time and space you could consult them for the origins of these names, however I can provide meanings and (approximate) pronunciations:

*CRIMTHANN (Modern: Criomhthann/Criofan) [kriffan]
"a fox" a male name
*SÁERLAITH (Saorlaith/Saorla) [sayrla or seerla]
"noble princess"
*EANLAITH (Éanlaith?) unable to find this one,
perhaps it is a made-up name. [aynla]
"bird-princess"?
*KEEFE anglicised form of CÁEM (Modern Caomh)[kayv-keev]
"precious, beloved, beautiful" Male name
*MUIRENN (Mod. Muireann) [mwirran]
?"sea-white" or "sea-fair" Female name
*GALVIN anglicised form of Gealbhán [gal(a)vaun]
"bright-white" male name
*LABHRÁS the Irish form of Laurence [low-raus; "ow" as in "now"]

Keefe is from where /w'/ got devoiced to /f'/, so to say 'keev' to 'keef'.

I would not agree on Labhrás as been 'low-raus'. If anything, the diphthong would be in the first syllable (due to the bh). I'v heard it as [Laur@s] or [ l̪ˠauɾəs] before

OK BaRNí,
I guess any time you try to spell something according to English orthography you are asking for trouble.
The "ow" can be [o:] as in "low" (íseal) or [au] as in "now". I don't have IPA characters so I was trying to work around them.
But since we talking about the name, it is (and was) pronounced several different ways according to the area:
in Munster it is [Lau'ra:s], in Ulster and Connacht is is pronounced ['Lau ra:s and ['Lau ras]. In Derry it was
pronounced ['Lav ras], in Omeath [Lo:ras] and in another area (possibly Clare) is was ['Lu:ra:s]. These examples are from Woulfe and Ciarán Ó Duibhin.

*CRIMTHANN (Modern: Criomhthann/Criofan) [kriffan]

Is "MTH" commonly pronounced "F"? I don't believe I've seen this yet.

['Lav ras] which you mean the voiced bilabial (to differentiate it from the diphthong of 'au'?)

'mhth' is usually f, I think, as in Ó Dumhthaigh (O Duffy) as I've seen in places, inclusing a shop in Mayo, charlestown I think

A Chairde,
Crimthann is the Old Irish form and I don't speak Old Irish but the modern form is Criomhthann and apparently one of the anglicizations was "Griffin". It was also anglicised Crohan. See Ó Corráin and Maguire ("Irish Names") for that one.
The older form of Ó Dufaigh (O'Duffy) was Ó Dubhthaigh. However it was also pronounced Duhig in Munster and possibly "Doohey" in SE Ulster.
I can't think of any other examples at the moment but I believe -mhth- and -bhth- were pronounced as f.
According to info received from Ciarán Ó Duibhin Labhrás was pronounced with a voiced bilabial in Derry.
Compare the surname Ó Labhraidhe anglicised as Lowry and Lavery.