I am not exactly sure what state they lived in when they got married. The first record of them in the US that I found was the 1880 Census. All the records I have for them put them in Bakerstown, Allegheny County, Pennsylvania and Richland, Allegheny County, Pennsylvania.
I did find one somewhat promising lead. I see a John Aiken married a Mary Bowick in 1873 in New York, but I am not sure if this is them. https://familysearch.org/pal:/MM9.1.1/F67Q-MNP
The date of the marriage is within the range on the census or very close.
My main problem is finding anything solid before they arrive on the 1880 Census.
I am hoping the death records I am sending for will give me some more information. And yes, I am going to try and get to the public library this week to see if I can view Mary's obituary. John's is going to be a bit tougher, but when I get the death record it should make things easier, then I can at least search by an exact date in 1905. I looked up some history of the paper and it was around back in 1905.
Thanks for the suggestion.