When applying for a US B1/B2 visa from Russia and you can fulfill most of the required documents but can only do partially one of the requirements i.e... The passport as one, the airfare for the third but you can only fulfill your earnings statement and your pay-stub at the time of your application, can the travel agent send proof of your financial means to the embassy when you show him/her that you have the funds?
There is really not much that can be deemed acceptable as proof of funds for the purpose of the visa. The issue is not just the availability of funds but also their provenance.
A consulate use paystubs as part of the proof that the applicant will return because they have a legitimate job and the bank statements to proof that the money that the applicant has come from legitimate sources, such as a job, and not from illegal or questionable activities.
There is also a related question related to Schengen visa application but similar logic would apply for the US: