The shop is being reworked and will be offering only books during the coming two weeks.

We assume that you have already seen this page?
https://glorian.org/connect/blog/incense#where-to-get-incense

One recommendation for incense was Nippon Kodo, which is so popular that you will even find it on Amazon.

Ah yes I did hear of them, I am glad you guys like them too. Okay and as for essential oils, rocky mountain oils are known to be very good, I see they are way more expensive than incense sticks, which makes me think they are of better quality?
Which form is better? Incense or essential oils, they are both convenient but why is the latter more expensive if the former is "stronger"

Essential oils take more to process and produce, hence the increase in price. Some people may have preferences and want to avoid sensitivities to smoke. Both are effective for cleansing, although burning incense is more powerful due to Fohat.