Comicxposure has released a coupon code that takes $5 off Amazing Spider-man Renew Your Vows #4 variant. This makes the color cover $9.99 and the black and white $14.99. This is for the Siya Oum variant cover.
The coupon code is: RNYV2015
And the full images were also released for all four covers for ASM Renew Your Vows #3 with cover dressing (logos and such)