Spark Plug covers-where to buy

Looks like PVL website also has the original NGK for 39.95.  

https://www.sparkplugs.co.uk/ngk-spark-plug-cap-vd05fmh-8425

https://www.ebay.com/itm/205263429450

https://www.motor-x.com/p/spark-plug-cap-ngk-vd05fmh

https://www.jmpbparts.com/sparkplug-cap-ngk-vd05fmh.html

https://classiccarrepublic.com/shop/service-parts/spark-plugs/ngk-vd05fmh-8425-spark-plug-cap/

https://www.easyparts.com/Ngk-Bougiedop-Vd05fmh-p33699230

I think even with overseas shipping most of these are cheaper than Lockwood.  Wonder why no US sources.  Ebay is out of stock.  Have you used the non-NGK versions of this?  I was wondering that if I changed out one that I should replace all for consistency

Thanks 

I would only change the ones that no longer measure correctly or don't have the correct pull-off force.

Looks like PVL website also has the original NGK for 39.95."

Yes as do other online stores BUT who wants to pay such a ridiculous price for something that can be substituted with another (conforming) product at about 1/4 the price.😈