Thank you for the question. If you cannot find a visa that allows your to simply immigrate to the UK, then you can look at attending the country on a visitor visa, you can get these for prolonged lengths of time. Once you have been in the Uk continuously without being resident in another country for a period fo 450 days, you can look at changing your status. Again, depending on your personal situation, there may be different routes to go about this, but you can come for 6 months without a visa in the first instance, depending on what you are doing in terms of study etc with your interests it may be possible to look at sponsorship from the UK. If you are finding, as you say, that your position is quite unique and nothing seems to apply to your personal circumstances, I would advise speaking with the UK home office, they are the governing body who would be able to give you specifics about your own situation. Given the vast costs, I would not look at instructing an immigration lawyer unless you feel it is absolutely necessary.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
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