It is sometimes called a gasket but you can call it what you want look into the open portion of your filter and it has an o-ring or quad seal fubber that seals the oi; from spraying out .
Good quick-lube shops require their employees to examine the filter when they remove it and also look at the mounting surface to make sure nothing is stuck to the block. AFA the reason it sticks , who knows . The "fix" is to examine the mating surface and a smear of oil to the seal on installation. You don'twant to lose an engine just because of this .
Make sure the filter wrench you buy works on the filter you are removing and you use the SAME brand oil filter you are installing. The "end" of the filter has to be the same design to work. I know , I have about 10 cup type filter wrenches and no brand has the same "end cap" size/design.
I Googled Shindy last night and saw plenty of choices . M/I is a top notch M/G dealership . I will have to check and see what they have .
The Bitubo rebuild sounds good too .
Easy , what does your manual call for ? My book calls for 20w50. W/that being said , we live in a free country.
Personally , I would run the Castrol .
IDK anything about Motorex brand oils.
I would go with an injector cleaning services . Using these companies will test before and after rates to show "if' needed and how bad they were . Find one company and stick with them. You need to keep your injectors and not buy these cheap alternatives !
I had this one co-worker make the perfect statement "When did you ever regret buying the best?" I have not forgotten this and will stick with it !