Greetings Bob:
This is Abdul from N & R Intl Inc. We have a Black Marble base that is 8 X 8 X 2. I am not sure how big base you need but this base will allow a good amount of space on the side as well as on the top assuming foot print of rail model is not too deep. You can laser this base and does not need to be color fill as the marble will turn frosty white when it is laser.
Let me know if you need more details or if you need a picture of this base.
Have a wonderful weekend.
Note: Our website address is etchedstone.net but we are experiencing a problem with google and microsoft edge. It works okay on firefox and safari.
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Abdul Amlani
N & R International Inc
Marietta GA
678.560.4088
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