Here is a list of character:

http://www.chise.org/ids-find?components=%26A-CDP-8CF0%3B

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With some search I found this website http://www.chise.org/.

I'll quote some of its intoduction here:

For freedom of character representation

The CHISE (CHaracter Information Service Environment) project is an open source research and development project aiming at realizing a next-generation character processing environment that is not restricted by general-purpose coded character sets by directly using various knowledge of characters. We attempt to realize a free and advanced character processing environment and conduct research and development as follows:

• Research on architecture
• Development of foundation system / application
• Development of character ontology and other datasets related about characters

It's basically in Japanese but the characters in Japanese and Chinese have the same origin.

It has a Chise IDS find, which can look up characters with a certain component. But for components that cannot be represented by Unicode, you have to find the ID of the component first.

So for your particular case, “益” can be looked up in the "CHISE-wiki character finder" on the main page, and then you get a detailed breakdown of "益". In the break down, you can find the component you are interested in. By clicking the component, you will be directed to a page of the component. And at the bottom of that page, there is such a button says "を含む漢字を探す (search) ". It is in Japanese and it means "find characters containing ...". By clicking search, you will get to the page on the top of this post, a list of characters that contains the component.

The top part of 「益」 is just a 「氺」 (水) rotated 90 degrees.

秦
簡

12.47
睡虎地秦簡
篆

皿部
說文解字東漢
隸

華山廟碑
　
楷


　

秦
簡

25.46
睡虎地秦簡
篆

水部
說文解字東漢
隸

郙閣頌
　
楷


　

This makes the top part of 「益」 just a variant of 「水」. Predictably, the character 「㳑」 is the variant with more standard components, although this character itself is not standard.

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Normally, a search for a list like the one in the question would also incorporate everything containing 「水」, just like a search for everything containing 「水」 would normally include everything containing 「氵」.

If you only want characters containing an arbitrary component 「Ｘ」, in general, I would advise against going through an ideographic description sequence decomposition database like CHISE or Pleco's component search containing 「Ｘ」, at least not without some due diligence checking later. The results which turn up are very misleading if you're not careful. For example, the search for 「⿱䒑八」 in CHISE literally turns up everything which

• contains regular script strokes which look like 「䒑」, an abbreviation for many things including 「艹」, on top of
• a bunch of regular script strokes which look like 「八」

「水」, written sideways or not, does not contain 「䒑」 and/or 「八」. There are other characters which contain the stroke sequence 「⿱䒑八」 like 「?」, which is an abbreviation/corruption of 「檐」.

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A cursory glance at some of the CHISE results shows that the number of encoded characters containing sideways 「水」 is quite limited. Apart from everything containing 「益」, that database lists

• 「?」 (variant of 「滅」 where the 「水」 is shifted to the bottom and rotated sideways)

  

• A few characters containing 「?」 (variant of 「涉」 where the 「水」 is shifted below 「止」 and rotated sideways)

  

  • 「?」 (variant of 「瀕」)

    

  • 「?」