Here are 10 plaids patterns.
Click on Design links to see design page for each pattern.
On The Design page, you can change any color on the pattern.
You can also get SVG for the pattern by click on the pattern (on Design page). It'll generate SVG format at bottom. You can then right click the SVG and save as .svg file.
BONUS: You can get extra virtually unlimited patterns by clicking the "Click here to get a new pattern" link on the Design page.