Telescopes are much more versatile than spotting-scopes, which you may suspect or know already. With a telescope, there are lots of eyepieces and other optical accessories available which enhance the experience immeasurably.
Your spotting-scope is grouped under the refractor category of telescopes. All other telescopes use mirrors, and are reflectors instead. A refractor with a larger aperture within your budget is not going to contain ED glass, therefore you will see false-colour, chromatic aberration, when viewing brighter objects; a purplish halo around Jupiter, for example, and the image of the planet a little less clear and sharp as a result.
You would see an improvement with a 102mm astronomical refractor; for examples...
That achromat(refractor) is shorter, and would exhibit more false-colour, but it would also be easier to store and transport. It comes with a simple-to-use alt-azimuth mount.
That achromat is longer, but would exhibit less false-colour, however it would also be harder to store and transport, the mount in particular. Although, that type of mount, an equatorial, would allow you to track the objects in the sky. The mount can be motorised, simply, to track for you automatically; just to track, and once you find an object manually. It is not a go-to.
The longer refractor is available as an OTA only... https://www.highpoin...r-ota-21088-ota
That way, you can place the refractor upon a simpler alt-azimuth... https://www.astronom...muth-mount.html
With that combination, or that of the shorter refractor and its alt-azimuth, there's a certain freedom in pointing the telescope to this object and that, most easily, and without having to worry with aligning an equatorial mount. However, there are pros and cons to both types of mounts.
Among the reflectors, a Newtonian, and usually mounted on a Dobson alt-azimuth, is "the best bang for the buck". Mirrors are easier to produce than lenses of clear optical-quality glass, and are therefore cheaper. For the price of the longer 4" refractor, just the OTA, no mount, you can get a 6"(150mm) Newtonian on a Dobson alt-azimuth mount...
...or an 8"(200mm), and still within your budget...
With a Newtonian, you would need to learn how to collimate it, perhaps initially upon its arrival, and on occasion thereafter. The refractors would not need to be collimated; normally, usually.
Recently, I got my own 127mm Maksutov. Maksutovs are oft used as spotting-scopes, for surveillance even...
...but they have very long focal-lengths. That one has a focal-length of 1900mm, and almost to that of a Celestron C8. As a result, they're a bit blind when used on a manual mount. They need help to see, to find things in the sky. They're usually placed on go-to mounts, but that's not a hard-and-fast rule. At the lowest power, only a small part of the sky is seen. They're very good however for seeing things up close, and closer still. They're like a microscope, but for the sky...
Now, that kit's mount is a bit small, not very supportive of the telescope, but you can get it and an Astro-Tech Voyager II alt-azimuth listed previously, and that combination will be at least $50 less than this kit...
You'd then have the little alt-azimuth, in addition, and for your spotting-scope.
Then, that same Maksutov also comes with an equatorial mount, and for less. That mount would be a bit more supportive of the telescope compared to the smaller alt-azimuth...