Wrapping Variables In Speech Marks

I am working on a date function, which takes a YYYY-MM-DD input and splits it into dd,mm,yyyy format. e.g:

string1 = "2006-10-20"

Function stripDate(str)
str_len = len(str)
if str_len = 10 then
str = replace(str, "-","")
str_yr = left(str,4)
str2 = right(str,4)
str_mo = left(str2,2)
str_dy = right(str2,2)
stripDate = str_dy & "," & str_mo & "," & str_yr
else
Exit Function
end if
End Function

test = stripDate(string1)
sample output: 20,10,2006

I then want to pass the sample output into another function, but in order to do that, the date variables must be split with speech marks as follows:

"20","10","2006"

but I can't work out how to include that in the stripDate function so that it wraps the variables in speech marks. Whenever I try to include the speech marks the code returns the usual error about unterminated string constants e.g. if I replace the final line of the above function with this: