Just getting an extension cable and placing your antenna outside up high as possible should greatly increase your antenna capability. Even if it's a stock antenna.
I'm sure there's better ones out there but these cables haven't steered me wrong yet.
TRENDnet Low Loss RP-SMA Male to RP-SMA Female Antenna Cable, 6 m (19.6 ft.), 3.0 dB Max Signal Loss, TEW-L106 black https://www.amazon.com/dp/B06ZXRWLXQ/ref=cm_sw_r_apan_glt_fabc_YSKVV708CWBN2Y0PXBXV?_encoding=UTF8&psc=1
Not sure how accurate it is, but heard someone saying (this one) in particular works as long as you get the "RP-SMA". I plan on trying it, but not getting my Vive until Xmas.
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