I am confused. I just want to make my amine so I can continue my reactions and form something else after that!
The main point that you need to understand is that alkylation of amines by SN
2 reactions with alkyl halides or (alkyl sulfonates) is not a good general method because it can be difficult to control the product distribution - you often get alkylation. Think about mixing MeI and ammonia - you will get a mixture of methylamine, dimethylamine, trimethylamine and tetramethylammonium iodide.
This is a classic problem discuessed in any organic textbooks, and there are several well established workarounds including: Azide displacement, Delepine reaction, Gabriel synthesis, reductive amination, reduction of an amide, Curtius rearrangement and Hoffman rearrangement. Look these up for some inspiration for your problem.
When you say reductive amination, I understand that, but I don't think I have any chemicals that will allow me to make my wanted amine with that reaction mechanism.
Design the route, then buy in what you need. The materials required for the purification of a messy SN
2 reaction may cost more than just buying the reagents for a well planned synthesis.
What eluent system should I use to isolate my monoalkylated amine?
That can only be determined experimentally.