Dear Tara Coile,
Thank you for posting your question on History Hub!
The Federal Government does not ordinarily create or maintain birth, adoption, death, marriage or divorce records. Such records are made and kept by State and local governments rather than the National Archives. We suggest searching substitute record sources such as probate records, church records, and newspaper records that may uncover more information about Abram Colby. Unfortunately, There's not much in the record following his testimony to Congress.
If you haven't done so already, I would check out Ancestry.com, which is a subscription-based service, but through partnerships with archives and libraries, offers free access at some locations. Using our access, I was able to locate a family tree with an Abram Colby that matches some of the data when know about Abram's age, and residence. Here are some screenshots of a public family tree containing some helpful information.
Also, be aware that misspellings were/are common on hand-written documents such as Census records. I believe in the 1870 Census, Abram is recorded as "Abraham." The Census records are also available on Familysearch.org which offers free memberships and access.
We hope this information is helpful. Best of luck on your research!