You can download dbSNP data in a vcf format for your organism of interest. Here is the link to human dbSNP in vcf format: ftp://ftp.ncbi.nlm.nih.gov/snp/organisms/human_9606/VCF/

You can follow this post then to retrieve VCF lines for a set of rs#

Retrieve Single Vcf From List Of Snp Rs#

I don't know what information you exactly want to have in the VCF file, but you could also think of using your rs IDs as input for the Ensembl VEP and downloading the resulting VCF file. That file probably contains more information than you want, but if that doesn't bother you ....