For standardized coefficients it is convenient to use the greek letter beta, therefore you could use simply the latin letter b (in italics) to denote unstandardized coefficients. For the standard errors you could put it SE_beta and SE_b for the standardized and unstandardized coeficients, respectively.

You can check the illustrative example in the following article (p885).

each path direct/indirect effect is actually an unstandardized coefficient, italicized as Boris mentioned.

http://www.quantpsy.org/pubs/preacher_hayes_2008b.pdf

In addition, it doesn't hurt to clarify for readers who are not familiar with statistical notation.  Simply say, "the standardized coefficient was....". 

This may help:

http://www.statisticssolutions.com/regression-table/

unstandardized B

standardized b or β