NACO question : Republic of Texas government vs state of Texas government

I feel like I should know the answer to this question since I catalog at the Texas State Library and Archives Commission, but I am at a loss.  We are cataloging a number of documents which originated during the Republic of Texas years (1836-1845).  That means there are documents published by the state of Texas and also documents published by the Republic of Texas.  The geographic authority heading for Texas includes this tag:

667 Includes old catalog headings: Texas (Province); Texas (Republic)

Please excuse my ignorance, but does that mean there once was a heading Texas (Republic) but it is no longer used?  What we are trying to establish is a heading for the Texas Department of State (not the current one for the state of Texas) but one for the Republic of Texas.  I see one document in OCLC with this heading:

Texas. ǂb (Republic) Dept. of State.

And there are others:

Texas. (Republic) Congress.

Texas (Republic). ǂb Congress. ǂb House.

Texas (Republic). ǂb Congress. ǂb Senate.

Texas (Republic). ǂb War Dept.

There are headings for the Provisional government as well, but that is different from the Republic government.

My question is:  How do we differentiate between the Republic and the State?

The Department of State for the state and the Department of State for the republic?  etc.

Thank you for your help.

Pat Fowler

Patsy D. (Pat) Fowler
SirsiDynix Unicorn System Administrator
Hosted site: GL3.1.3
Head, Cataloging Department
Texas State Library and Archives Commission
Austin, Texas

(The opinions expressed are my own & not necessarily those of my employer.)