"Unbundled" and "coaching" are red herrings here. What I think you really want to know, and it is a very good question, is whether an attorney's advice, rather than take-the-case full representation, is available to you. The answer to that question is "yes."
Many, many lawyers offer consultations for an hourly fee. But you should do some homework first in order to realize the maximum benefit of such service. First, you should look hard for a solo practitioner or relatively small law firm (usually the most flexible about kinds of services available) who specializes in the kind of law and case that yours involves. You may even want to consult court records and try to locate an attorney who has previous litigation experience against the company you are suing in a case featuring claims relatively similar to yours.
When you have found a few names that you feel may be right for you, call and ask whether you can schedule an appointment for advice only, for an hourly fee. Many attorneys and firms offer an initial consultation (usually no more than an hour) at no charge. And some will speak with you on the phone first, just to be sure that your issue is one that they are likely to able to assist with.
Be sure to craft in advance of your meeting a short straight-forward and brutally candid statement describing the facts, how you envision proving your allegations, and what it is you want from the lawsuit. Describe for the lawyer the kind of intermittent or periodic conferences that you would like to engage for. Expect that the lawyer may tell you frankly that the case is too complex for you to self-represent. In that event, the attorney may decline further participation and may refer you to some other resources.
If the attorney does not feel that you are inevitably getting in over your head by going pro per, you may be able to set up a schedule, probably tied to case events and case progress, for advice conferences.
You should not expect "coaching" in any advisory conference. Few attorneys will take on the task of teaching lawyering skills and techniques in this situation because such skills cannot be learned or applied simply by benefit of discussions. But you will not have difficulty finding advice as to case sequence and procedure, case evaluation, and relevant law.
If you do enter into an attorney-client relationship for advice only, you should expect that the lawyer will ask you to sign a very specific "engagement letter," which sets out the strict limits of the legal services to be provided and plainly describes the services not engaged for.
A final point: don't expect that you will find an attorney who is willing to take on individual elements of the case, such as just settlement negotiations, or just trial at the end of discovery and motion practice. That model would be wholly untenable for both parties for many reasons.
It is likely that if your case has merit and a potentially worthwhile recovery, that you should think twice -- and then twice more -- about going pro per. If it's a good case, there is an attorney or many attorneys who will take it on contingency. If no one will, well, you have just had a free case evaluation there.
Good luck to you.