Those are essentially genomic coordinates, right? I think you could just parse out the extra crap then give it to VEP to create a valid VCF: https://m.ensembl.org/info/docs/tools/vep/vep_formats.html#default

I've done similar things to get wacky formats into VCF

At a minimum, you can make a vcf file with the chromosome, start position, ref and alt, which you have. See the full specification to find out more. For a minimally working example, you can format it like so:

#CHROM POS ID REF ALT QUAL FILTER INFO
20 14370 . G A . . .

The other required fields are replaced with a .. Here's a way you could convert the input:

$ cat variants.txt \
          | sed 's|ins|\t.\t|g' \
          | sed -e 's|del\([ACGT]\)|\t\1\t.|g' \
          | sed -e 's|\([ACGT]\)>\([ACGT]\)|\t\1\t\2|g' \
          | sed 's|:g\.|\t|g' \
          | sed 's|_[0-9]\+||g' \
          | sed 's|$|\t.\t.\t.|g' \
          | awk 'OFS="\t" {print $1,$2,".",$3,$4,$5,$6,$7}'

17      7674180 .       C       A       .       .       .
17      7675997 .       G       T       .       .       .
17      7676257 .       G       A       .       .       .
17      7676088 .       G       C       .       .       .
17      7676215 .       G       A       .       .       .
17      7676152 .       C       .       .       .       .
17      7676381 .       C       A       .       .       .
17      7670712 .       G       .       .       .       .
17      7670716 .       C       G       .       .       .
17      7676264 .       .       A       .       .       .

Now instead output to a file (e.g. add > example.vcf at the end of your file) and you should have a VCF file. Some programs might require your to add the header information (lines that start with # in that specification document) so you might have to tweak that a bit.